A cobpobation of massa



April 30, 1929. R, H MAURER 1,711,421

PILOT CUT-OFF FOR GAS BURNERS Filed sept. 1 6, 1927 InL/'etlvf' QW HMP 'E' .5 @Wmmy Patented Apr. 3o, 19.29.

UNITED STATES Im'rala'r OFFICE.

RUFS H. MAURER, OF BROOKLINE, MASSACHUSETTS, ASSIGNOR TO SPENCER THER- MOSTAT COMPANY, 0F CAMBRIDGE, MASSACHUSETTS, A CORPORATION 0F MASSA- CHUSETTS.

l PILQT CUT-OFF FOR GAS -BILIRN'ERS Applicationl led September 16, 1927. Serial' No. 219,941.

This invention relates to gas burners and more particularly to heating gas burners provided with pilots and wlth an automatic means of cutting 4oil' the flow o gas in'the event that the pilotis extinguished.

Heating by gas is -now very common for .l water heaters, boilers, stoves and domestic furnaces and it is custm'ary in many of these installations to vary the heat applied by therinostatic o r other means; so that as the burners are often relatively inaccessible, and itis j customary to provide a pilot light adjacent t0 the burner if it is extinguished and it is desired to relight it. It sometimes happens that during the time the main burner is extinguished by the thermostatic or other means, the pilot accidentally goes out, so that when the i'ow of gas tothe main burner is reestablished, it is not ignited, but escapes to the surrounding parts of the building in -which the burner is located. v

Among the objects of the invention, therefore, are to provide an automatic shut-01T provide a simple, cheap and eicient mecha-` nism to accomplish `the above results; and generally to improve devices of'th1s character.v A A Other objects .and advantages of the invention will be apparent from the followlng specifications and yappended claims when taken in conjunction with the accompanying drawings, in which:

Fig. 1I is an elevation of-the gas burner partly broken away to show the pilot, thermo stat and valve structure in vertical section;

Fig. 2 isla combined elevation and section on the line 2-2 in Fig. 1; and

Fig. 3 is an. enlarged view of the thermostatic disk. i i

I have shown my invention 'in connection with an annular ring type gas or gas and lair burner 1 having a plurality of series of opposed jet nozzles 2 and a as inlet 3, but it may equall well be appli'e to other types of burners. pilot nozzle 4 is formed ladjamixture supply pipe 7 and having a. connec tion at 8 with an inlet opening 3 ,of the burner 1. The housing 5 is provided with a dividing lwall'9 having a passage 10 therethrough adapted to be closed by a valve 11, which may be constructed of any suitable material, for example rubber, and may have a peripheral flange 12, which,`when the valve is closed, is turned up, as shown at 12a (Fig. 2). A rod 13 is fixed to the valve 11 by a nut engaging a reduced threaded extension of the rod 14 or in any other desired manner, and extends through a suitable bearingopening in the wall 9 and thence through an enlarge'd opening 15 in one side wall 16 of the housing 5. The wall 16 may be provided with an outwardly extending annular flange 17, threaded on its outer side for engagement with an enlargement 18, which may be integral wit-h tlie pilot nozzle 4.

I provide thermostatic-means in heat conducting relationship with the nozzle 4 of the pilot to actuate the rod 13 and open and close the valve. This tllermostatic means is preferably a disk 19, which is engaged at its periphery between the flange 17 and a shoulder formed on the enlargement 18 and is perforated, as shown at 20, to permit thev passage of gas therethrough to sustain the pilot light. y The rod 13 is connected .to the center of the gether, the materials such as iron and brassl of the respective disks having different coefficients of expansion. The disk 2O is normally f cupped (as by swaging) in such direction that the` component part having the higher coetlicient of expansion is on the concave side. Consequently upon raising the temperature of the disk the unequal expansion of the materials forming the 'disk will cause a tendency to flatten the cupped surface until at a presnap back at a lower-temperature (e. g. 100" F.) Suitable materials are sheet brass an'd nickel steel having a thickness yof .O05 and .005 inches respectively and suitable cupping for a disk '0A inches in diameter is .02 inches.

It will be understood however that the present invention is not limited to any particular combination of materials having different thermal coeflicients of expansion but is intended to embrace in its scope any combination of materials having dissimilar thermal coefficients of expansion sufficient to cause the reversal of curvature/ Furthermore, the two materials comprising the composite thermostatic disk may be secured together in any desired manner by riveting, soldering, brazing, or otherwise although it is preferred to unite the materials comprising the disk by welding or similar means to secure a substantially indivisible sheet.

I provide a separate independent source of gas for the pilot light here shown as a supply duct 22 which may connect with the main gas pipe7 at the other side of the valve shown, and which may be suitably xed in the housing 5 by threading or in any other suitable manner, the duct 22 bein connected by a bore 23 with a space at one si e of the thermostatic disk 19, so that the pilot will receive a con- Sgtafnt supply of gas whether the burner is in operation or not, and during the time it is in operation the pilot will receive a large supply of gas through the opening 15 from the interior of the housing 5. r

The supply of gas through the tube 22 is designed to be suflicient to maintain the pilot and thermostat in a heated condition so that the parts are as shown in Fig. 1', that is, with the valve 11 in open position. However, if for any' reason the pilot should be extinguished, the thermostatic disk will cool olf' and then suddenly reverse its concavity,

drawing the rod 13 to the right and closing the valve as is shown in Fig. 2. To relight the burnerit is merely necessary to relight the pilot and the thermostat will when it is again heated snap back to the position shown in Fig. 1, whereupon the valve will be opened and gas may lflow to both the pilot and the burner which will enlarge the pilot flame and light the main burner. As the pilot receives an additional supply of gas during the time device may be made without departing from the spirit of the invention, I do not wish to be limited except by the scope of the appended claims. I claim: 1. The combination with a gas burner and a supply pipe therefor of a pilot burner adapted to light the main gas burner, a valve housing having passages therethrough from said supply pipe to both said main burner and said pilot, a valve in said housing controlling the flow of gas through both of said passages, a thermostat associated with said pilot adapted abruptly to close said valve if said pilot is accidentally extinguished, and

a separate additional supply of gas for said a supply pipe therefor of a pilot burner' adapted to lightv the main gas burner, avvalve housing having passages therethrough from said supply pipe to both said main burner and said pilot, a valve in said housing controlling the flow of gas through both of said passages, a perforated disk thermostatinterposed inthe gas passage to said pilot and in heat conducting relation with the walls thereof, and a direct connection between the thermostatic disk and said valve, whereby the valve is automatically and abruptly closed if the pilot is extinguished.

3. The combination with .a gas burner and a supply pipe therefor 4of a pilot burner positioned to light the main gas burner, a valve housing having passages therethrough from said supply pipe to both said main burner and said pilot, a/ valve in said housing controlling the low'of gas through both of said passages, a perforated bi-metallic disk thermostat concentrieally vmounted in an enlargel ment of the gas passage tosaid pilot and in passages,` a cupped perforatedv 'bi-metallic disk thermostat concentrically mounted in an enlargement in the gas passage to said pilot and having its periphery in heat con- `ducting relationship with the Walls of said burner Whenever gas is supplied thereto and enlargement, a rod having a bearing in a whereby said Valve is closed completely and part of said housing connecting the center abruptly if the pilotis extinguished. 10 of the thermostatic disk rigidly with said Signed by me at Cambridge, Mass., this 5 valve, and means for supplying a separate 14th day of September, 1927.

- constant gas feed to said pilot, whereby the pilot is normally operative to relight the RUFUS H. MAURER. 

